a paper on “Portable Aeroplane and Trench Radio Sets” with special consideration of a type of apparatus developed by the author for utilizing direct currents in producing musical notes without the use of a motor generator set and revolving spark gaps. Mr. Dubilier has recently returned from France and England where he made experiments with these sets. He very interestingly described in detail, with lantern slides and apparatus, the installations now being used by the Allies for directing artillery fire, and communicating between trenches.
Mr. A. S. Blatterman presents very interesting paper before Institute of Radio Engineers.
At the meeting of the Institute of Radio Engineers, held Jan. 5th., a. paper on “Variations in Nocturnal Transmission” was presented by Mr. Blatterman. It gave a very interesting account of experiments in nocturnal transmission which have been carried on between the University of North Dakota and Washington University in St. Louis, Mo. A number of peculiar effects of value to experimenters in the radio field were quite clearly brought out.The Club invites all amateur radio stations in the United States to communicate with them through their secretary, Thomas Havard, 48 John St., New Rochelle, N. Y.
Receiving with a Pancake Tuner
EDITOR’S NOTE: Mr. House is a firm advocate of the pancake type coils. In this article he tells of, the excellent work which may be done and he gives a list of amateur call letters he copied in one evening. Many of our readers may be surprised to see their call letters here as they do not all know their long distance records.
IT is generally understood that the pancake receiving coils are not an efficient type. The writer has been using one for some time and is very well satisfied. In fact, recently, he built over a whole new receiving set into pancake style; even to the 10,000 meter set for undamped waves.
The following is a list of stations that the writer hears almost every night, using the single audion (no amplifying arrangement). The audion is a poor one having been knocked down several times so that it sometimes does not work for several days at a time: 8ER, 8EZ, 8GV, 8XAU, 8LF, 8YO, 8PL, 8AMN, 8XP, 8SN, 8ZN, 8AAE, 8LE, 8PB, 8MW, 8FW, 8KP, 8PE, 8PC, 8OZ, 8LD, 8RD, 8CT, 8PP, 8TD, 8MV, 8CR, 8AD, 8PW, 8MZ, WP, WPR, 8JA, 8GG, 8CW, 8ABO, 8AHR, 8CB, 8LW, 8NH, 8US, 8NA, 8CL, 8WP, 8YO, 8GU, 8KU, 9AC, 9YN, 9BD, 9NF, 9TM, 9GY, 9IT, 9AA, 9DU, 9AAB, 9GHS, 9NN, 9CY, 9SY, 9SP, 5BJ, HED, HB. The writer has also heard 5BJ with Galena; also 8AEZ, 8NH, and 8WP very easily. Some of these stations are using as low as one-quarter kilowatt sets. It may be of some interest to the operators to know that they have been heard so far with their sets. Most of their messages came in quite loud; easily loud enough to be read.The writer has also heard NPF, Cape Blanco, Oregon, on a 600 meter wave. His
coil takes in 6OO meter waves and he therefore gets all of the Lake boats and stations around the lakes, even as far as Port Arthur. He hears NAA 1oud enough at times to be able to read him ten to fifteen feet from the phones. His aerial consists of four wires, five feet apart. One hundred feet flat top, fifty feet high, inverted L type. The readers may be interested to know that twenty-eight of the above stations were received between 8:45 and 9:20 on the evening of January 29th.